U.S. Pat. No. 3,138,904 to Earl E. Burford entitled "METHOD AND APPARATUS FOR TYING PACKAGES AND WRAPPING MATERIALS;" U.S. Pat. No. 3,059,670 to Charles E. Burford and Leonard W. Burford entitled "WIRE TWISTING TOOL;" U.S. Pat. No. 3,919,829 to Leonard W. Burford and Charles C. Burford entitled "APPARATUS FOR TYING PACKAGES AND WRAPPING MATERIALS;" and U.S. Pat. No. 4,856,258, which issued Aug. 15, 1989 to Charles E. Burford and Jimmy R. Frazier entitled "WIRE TYING DEVICE" disclose apparatus used for closing a plastic bag by attaching and twisting a wire-like ribbon about the neck of the bag.
Bag tying devices of the type disclosed in the aforementioned patents are commercially available from Burford Corporation of Maysville, Okla. The tying devices are generally constructed to receive packages such as loaves of bread at speeds of for example one hundred (100) packages per minute. The design of the bag tying devices requires careful consideration of the mass, acceleration, deceleration and momentum of the moving parts of the tying device. Further, precise synchronization of parts in subassemblies of the tying devices must be maintained throughout a tying cycle if the device is to operate effectively.